package org.json.simple.parser;

import java.io.IOException;

/**
 * A simplified and stoppable SAX-like content handler for stream processing of
 * JSON text.
 * 
 * @see org.xml.sax.ContentHandler
 * @see org.json.simple.parser.JSONParser#parse(java.io.Reader, ContentHandler,
 *      boolean)
 * 
 * @author FangYidong<fangyidong@yahoo.com.cn>
 */
public interface ContentHandler {
    /**
     * Receive notification of the beginning of JSON processing. The parser will
     * invoke this method only once.
     * 
     * @throws ParseException
     *             - JSONParser will stop and throw the same exception to the
     *             caller when receiving this exception.
     */
    void startJSON() throws ParseException, IOException;

    /**
     * Receive notification of the end of JSON processing.
     * 
     * @throws ParseException
     */
    void endJSON() throws ParseException, IOException;

    /**
     * Receive notification of the beginning of a JSON object.
     * 
     * @return false if the handler wants to stop parsing after return.
     * @throws ParseException
     *             - JSONParser will stop and throw the same exception to the
     *             caller when receiving this exception.
     * @see #endJSON
     */
    boolean startObject() throws ParseException, IOException;

    /**
     * Receive notification of the end of a JSON object.
     * 
     * @return false if the handler wants to stop parsing after return.
     * @throws ParseException
     * 
     * @see #startObject
     */
    boolean endObject() throws ParseException, IOException;

    /**
     * Receive notification of the beginning of a JSON object entry.
     * 
     * @param key
     *            - Key of a JSON object entry.
     * 
     * @return false if the handler wants to stop parsing after return.
     * @throws ParseException
     * 
     * @see #endObjectEntry
     */
    boolean startObjectEntry(String key) throws ParseException, IOException;

    /**
     * Receive notification of the end of the value of previous object entry.
     * 
     * @return false if the handler wants to stop parsing after return.
     * @throws ParseException
     * 
     * @see #startObjectEntry
     */
    boolean endObjectEntry() throws ParseException, IOException;

    /**
     * Receive notification of the beginning of a JSON array.
     * 
     * @return false if the handler wants to stop parsing after return.
     * @throws ParseException
     * 
     * @see #endArray
     */
    boolean startArray() throws ParseException, IOException;

    /**
     * Receive notification of the end of a JSON array.
     * 
     * @return false if the handler wants to stop parsing after return.
     * @throws ParseException
     * 
     * @see #startArray
     */
    boolean endArray() throws ParseException, IOException;

    /**
     * Receive notification of the JSON primitive values: java.lang.String,
     * java.lang.Number, java.lang.Boolean null
     * 
     * @param value
     *            - Instance of the following: java.lang.String,
     *            java.lang.Number, java.lang.Boolean null
     * 
     * @return false if the handler wants to stop parsing after return.
     * @throws ParseException
     */
    boolean primitive(Object value) throws ParseException, IOException;

}
